As network systems advance, various devices installed in the house or the office can be used through wireless or wired connection. For example, by use of Universal Plug and Play (UPnP), a Personal Computer (PC), a terminal, and a smart television in the house can share data to simplify home network functions.
In such a home network, a control point can receive a notification message from each individual device and detect every device connected to the network. For example, the control point detects the connection status of each device by multicasting a Method for Search Request (M-SEARCH) message to every device on the network and receiving a response message such as an alive message and a byebye message, from each device in reply to the M-SEARCH message.
However, since the M-SEARCH message transmitted from the conventional control point to the device and the response message in response to the M-SEARCH message transmitted from the device to the control point are transmitted only once, packets are frequently lost. As a result, the control point may not be able to discover some devices that actually exist in the network.
The notification message includes a maximum time for waits (MX) value. The MX value relates to a response time when the device sends the notification message to the control point. With a fixed MX value, the related art cannot reflect the actual network environment. For example, the fixed response time is used regardless of the number of the devices in the network. The response time is lengthened even with the small number of the devices. Consequently, it takes more time for the control point to detect the connection status of the device in the network.